See https://bugs.freedesktop.org/show_bug.cgi?id=47792;
should become obsolete with the next release.

diff -u luit-1.1.1.orig/sys.c luit-1.1.1/sys.c
--- luit-1.1.1.orig/sys.c	2012-03-23 05:23:07.000000000 +0100
+++ luit-1.1.1/sys.c	2013-11-27 22:45:53.000000000 +0100
@@ -20,6 +20,8 @@
 THE SOFTWARE.
 */
 
+#define _XOPEN_SOURCE 600
+
 #ifdef HAVE_CONFIG_H
 # include "config.h"
 #endif
>
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<tr><td><span title='2019-01-06 15:42:05 +0200'>2019-01-06</span></td><td><a href='/guix/commit/gnu/packages/unrtf.scm?id=30e06c2cee92fa9a9b9e86bb8bf9c3e8d458ef9b'>gnu: unrtf: Update to 0.21.10.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/unrtf.scm (unrtf): Update to 0.21.10.
[source]: Remove patch, remove snippet.
[license]: Update to gpl3+.
* gnu/packages/patches/unrtf-CVE-2016-10091.patch: Remove file.
* gnu/local.mk (dist_patch_DATA): Remove it.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2018-03-16 09:08:31 -0400'>2018-03-16</span></td><td><a href='/guix/commit/gnu/packages/unrtf.scm?id=6cbee49d6668eb7fd738080666f66febfce8c7e8'>gnu: All snippets report errors using exceptions, else return #t.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/admin.scm, gnu/packages/algebra.scm, gnu/packages/audio.scm,
gnu/packages/backup.scm, gnu/packages/base.scm,
gnu/packages/bioinformatics.scm, gnu/packages/cdrom.scm,
gnu/packages/chez.scm, gnu/packages/code.scm, gnu/packages/compression.scm,
gnu/packages/cross-base.scm, gnu/packages/crypto.scm, gnu/packages/cups.scm,
gnu/packages/databases.scm, gnu/packages/dns.scm, gnu/packages/emacs.scm,
gnu/packages/emulators.scm, gnu/packages/engineering.scm,
gnu/packages/enlightenment.scm, gnu/packages/fpga.scm,
gnu/packages/freedesktop.scm, gnu/packages/ftp.scm, gnu/packages/games.scm,
gnu/packages/gcc.scm, gnu/packages/geo.scm, gnu/packages/ghostscript.scm,
gnu/packages/gl.scm, gnu/packages/glib.scm, gnu/packages/gnome.scm,
gnu/packages/gnuzilla.scm, gnu/packages/graphics.scm, gnu/packages/gtk.scm,
gnu/packages/guile.scm, gnu/packages/irc.scm, gnu/packages/java.scm,
gnu/packages/kerberos.scm, gnu/packages/linux.scm, gnu/packages/lisp.scm,
gnu/packages/lxde.scm, gnu/packages/machine-learning.scm,
gnu/packages/mail.scm, gnu/packages/maths.scm, gnu/packages/messaging.scm,
gnu/packages/monitoring.scm, gnu/packages/mp3.scm, gnu/packages/music.scm,
gnu/packages/netpbm.scm, gnu/packages/networking.scm, gnu/packages/node.scm,
gnu/packages/nvi.scm, gnu/packages/ocaml.scm, gnu/packages/pdf.scm,
gnu/packages/perl.scm, gnu/packages/php.scm, gnu/packages/plotutils.scm,
gnu/packages/pretty-print.scm, gnu/packages/profiling.scm,
gnu/packages/pulseaudio.scm, gnu/packages/python-crypto.scm,
gnu/packages/python.scm, gnu/packages/qt.scm, gnu/packages/robotics.scm,
gnu/packages/sawfish.scm, gnu/packages/scanner.scm, gnu/packages/scheme.scm,
gnu/packages/scribus.scm, gnu/packages/sdl.scm,
gnu/packages/serialization.scm, gnu/packages/shells.scm,
gnu/packages/slang.scm, gnu/packages/smalltalk.scm, gnu/packages/ssh.scm,
gnu/packages/sync.scm, gnu/packages/syncthing.scm, gnu/packages/tbb.scm,
gnu/packages/terminals.scm, gnu/packages/texinfo.scm,
gnu/packages/text-editors.scm, gnu/packages/textutils.scm,
gnu/packages/tls.scm, gnu/packages/unrtf.scm,
gnu/packages/version-control.scm, gnu/packages/video.scm,
gnu/packages/vpn.scm, gnu/packages/web.scm, gnu/packages/wm.scm,
gnu/packages/wxwidgets.scm, gnu/packages/xdisorg.scm, gnu/packages/xorg.scm:
In all snippets, report errors using exceptions, or else return #t.
</span></span></td><td>Mark H Weaver</td></tr>
<tr><td><span title='2017-03-30 01:30:16 +0200'>2017-03-30</span></td><td><a href='/guix/commit/gnu/packages/unrtf.scm?id=6fd52309b8f52c9bb59fccffac53e029ce94b698'>gnu: Use HTTPS for almost all gnu.org HOME-PAGEs.</a><span class='msg-avail'>...<span class='msg-tooltip'>All HTTP gnu.org (and supported subdomain) HOME-PAGEs changed to HTTPS.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>